1. Field of the Invention
The present invention relates generally to manufacturing a form on the end of a shaft, i.e., blind spline tools mounted in tool holders, and more specifically to securing punches and dies to tool holders in individual or multiple tool arrangements.
2. Description of the Prior Art
Blind spline tools, i.e. punches and/or dies, individually or in multiple tool arrangements, have traditionally been held in position by precision grinding the major diameter or minor diameter of the cutting tool to very precise tolerances and mounting the cutting tool into tool holders having precision bores or pilots. Radial location is generally established by using a precision "V" slot or keyway. The "V" or keyway is manufactured in relation to the profile of the cutting tool and positioned central to the precision ground inside or outside diameter of the cutting tool. Most tools are retained by socket head cap screws threaded into the base of the tool holder. FIG. 6 shows such a prior art arrangement. A cylindrical cutting tool 100 is shown having a precision ground outer diameter 102 and an inner form ground master spline 104 which defines the cutting surface. The cutting tool 100 is secured to a cutting tool mounting block or holder 106 by securing bolts 108. The tool holder has a cylindrical cavity 109 with a diameter closely toleranced to the outer diameter 102 of the cutting tool 100. While the securing bolts 108 establish a location in a plane transverse to the axis of the cutting tool 100, the radial position of the cutting tool 100 still needs to be accurately positioned. For this purpose a "V" notch 110 is typically used to provide such radial positioning. A securing member 112 is formed on the tool holder 106 so that the "V" notch 110 in the cutting tool mounts therein to provide the radial position of the cutting tool 100 with respect to the tool holder 106.
To accommodate for the loss of the location in the transverse plane of the cutting tool when the cutter is sharpened by grinding the top of the cutting tool 100, a riser shim (not shown) is mounted adjacent to the bottom of the tool between the cutting tool and the tool holder by cap screws 107. This riser shim, which in thickness represents the metal removed from the top in sharpening the cutting tool, is usually attached to the bottom of the cutting tool after it is sharpened. Clearance holes for the screw heads which retain the riser shims to the cutting tool are provided in the tool holder.
To prevent a setup man from mounting the wrong cutting tool 100 in the wrong mounting block 106, a selective interference is provided in the cutting tool mounting block cavity. This selective interference is most commonly accomplished by having a dowel pin 105 located in and protruding from the top face of the tool holder 106 which mates with a corresponding hole in the bottom of the cutting tool 100 in such a manner as to interfere with all but the correct cutting tool. The correct cutting tool will have a clearance hole in a predetermined location with respect to the "V" notch and the mounting hole pattern to receive the dowel pin protruding from the top face of the tool holder and therefore only the correct cutting tool will fit in a specific cavity in the tool holder.
To remove the prior art cutting tool 100 from its tool holder 106 it is required that the securing bolt 108 be removed, and the securing member 112 removed or retracted from the "V" notch 110. often the prior art cutting tool requires the use of jack screws to remove or lift the cutting tool 100 from the cavity in the precision tool holder 106. The jack screws are required since the cylindrical cavity 109 in the tool holder 106 is precision ground to very close tolerances to match the outer diameter 102 of the cutting tool 100. The need for the various accurate positioning surfaces and associated retaining devices results in an expensive cutting tool which is time consuming to remove from its tool holder. Accordingly, what is needed is a cutting tool which is inexpensive to manufacture and easy to install and/or remove from its tool holder as well as which offers more accuracy for positioning the cutting tool on the tool holder.